1. Field of the Invention
The present invention relates to a capacitive transparent touch sheet used in a capacitive touch panel and more particularly relates to a capacitive transparent touch sheet having high durability and wherein electrodes, which are formed in the capacitive transparent touch sheet, are not visualized as a pattern when the capacitive transparent touch sheet is adhered onto a transparent base material.
2. Background Information
Conventionally, capacitive touch panels are used as touch panels. FIG. 11 is an exploded oblique view of a conventional capacitive touch panel, and FIG. 12 is a plan view of the conventional capacitive touch panel. With reference to FIG. 11, a conventional capacitive touch panel 200 is configured by adhering together an upper part conductive sheet α, which comprises an upper part base material 100 and upper part electrodes 101, and a lower part conductive sheet β, which comprises a lower part base material 110 and lower part electrodes 111. Furthermore, the upper part conductive sheet α and the lower part conductive sheet β are adhered together such that the upper part electrodes 101 and the lower part electrodes 111 cross one another (See, e.g., Japanese Unexamined Patent Application Publication No. H7-171408).
However, the upper part electrodes 101 and the lower part electrodes 111 are formed separately and both have a constant thickness. Consequently, in the conventional capacitive touch panel 200, the thickness of the locations at which the upper part electrodes 101 and the lower part electrodes 111 cross, namely, the thickness of intersecting portions γ between the upper part electrodes 101 and the lower part electrodes 111, is greater than the thickness particularly of locations δ at which the upper part electrodes 101 and the lower part electrodes 111 are not formed.
As a result, steps arise in the surface of the touch panel 200, and therefore, there is a problem in that, when shimmering light is radiated to the touch panel 200, the light is refracted by the step portions and the entire touch panel 200 adversely appears as if it is wavy.
Furthermore, there is a problem in that, because the intersecting portions γ are thicker than the other portions and form protruding shapes, fatigue accumulates over repeated use and thereby short circuits adversely occur during usage.
To solve the aforementioned problems, a method is known that adheres a cushioning sheet, which eliminates the steps, to the surface of the upper part conductive sheet α or the lower part conductive sheet β; however, in this method, there is a problem in that the overall thickness of the touch panel 200 increases, and therefore the touch panel 200 cannot be made compact.
In addition, there is also another method that improves the visibility of the touch panel 200 by reducing the thickness of the upper part electrodes 101 and the lower part electrodes 111, thereby reducing the steps created at the intersecting portions γ as much as possible; however, in this method, there is a problem in that, because the resistance value of the electrodes adversely increases commensurately with the reduction in the thickness of the electrodes, the sensitivity of the touch panel 200 adversely decreases.